fix(crystal): remove travis.yml file

Author: n-rodriguez

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CrystalClientCodegen.java

@@ -309,7 +309,6 @@ public void processOpts() {
         supportingFiles.add(new SupportingFile("README.mustache", "", "README.md"));
         supportingFiles.add(new SupportingFile("git_push.sh.mustache", "", "git_push.sh"));
         supportingFiles.add(new SupportingFile("gitignore.mustache", "", ".gitignore"));
-        supportingFiles.add(new SupportingFile("travis.mustache", "", ".travis.yml"));
         supportingFiles.add(new SupportingFile("shard.mustache", "", "shard.yml"));
 
         // crystal spec files

modules/openapi-generator/src/main/resources/crystal/travis.mustache

@@ -1,5 +1,4 @@
 .gitignore
-.travis.yml
 README.md
 git_push.sh
 shard.yml